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Abstract:

A display apparatus capable of adjusting the time for detecting input
signals from an external input source is provided. The display apparatus
includes a signal detector which checks a plurality of input sources in
sequence for a predetermined basic time and detects signals input from
the plurality of input sources, and a controller which controls the
signal detector to adjust the basic time and recheck the plurality of
input sources if no signal is detected within the basic time.
Accordingly, it is possible to recognize an input source from which input
signals are detected late.

Claims:

1. A display apparatus comprising:a signal detector which checks a
plurality of input sources in sequence for a predetermined basic time and
detects signals input from the plurality of input sources; anda
controller which controls the signal detector to adjust the basic time
and recheck the plurality of input sources if no signal is detected
within the basic time.

2. The display apparatus as claimed in claim 1, wherein the signal
detector checks the plurality of input sources in a predetermined order.

3. The display apparatus as claimed in claim 1, wherein the controller
applies a predetermined maximum allowable time if no signal is detected
within the basic time.

4. The display apparatus as claimed in claim 3, wherein the signal
detector performs the detecting operation a predetermined number of
times,wherein, if no signal is detected for the predetermined number of
times, the controller applies the predetermined maximum allowable time to
a last checking phase of each of the plurality of input sources.

5. The display apparatus as claimed in claim 3, wherein the controller
calculates a maximum necessary time which is required until signals are
input from each of the plurality of input sources within the maximum
allowable time.

6. The display apparatus as claimed in claim 5, further comprising a
storage unit which stores a reference time which is defined considering
the maximum necessary time,wherein the controller controls the signal
detector to detect signals by applying the stored reference time to each
of the plurality of input sources.

7. A control method of a display apparatus, the method comprising:checking
a plurality of input sources in sequence for a predetermined basic time
and detecting signals input from the plurality of input sources; andif no
signal is detected within the basic time, adjusting the basic time and
rechecking the plurality of input sources.

8. The control method as claimed in claim 7, wherein the detecting
operation checks the plurality of input sources in a predetermined order.

9. The control method as claimed in claim 7, wherein the rechecking
operation applies a predetermined maximum allowable time if no signal is
detected within the basic time.

10. The control method as claimed in claim 9, wherein the detecting
operation is performed a predetermined number of times,wherein, if no
signal is detected for the predetermined number of times, the rechecking
operation applies the predetermined maximum allowable time to a last
checking phase of each of the plurality of input sources.

11. The control method as claimed in claim 10, wherein the rechecking
operation calculates a maximum necessary time which is required until
signals are input from each of the plurality of input sources within the
maximum allowable time.

12. The control method as claimed in claim 11, further comprising:storing
a reference time which is defined considering the maximum necessary time;
anddetecting signals by applying the stored reference time to each of the
plurality of input sources.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This application claims priority from Korean Patent Application No.
10-2008-103502, filed on Oct. 22, 2008, in the Korean Intellectual
Property Office, the disclosure of which is incorporated herein by
reference in its entirety.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]Apparatuses and methods consistent with the present invention relate
to a display apparatus and a control method thereof, and more
particularly, to a display apparatus which is capable of adjusting the
time required for detecting input signals from an external input source,
and a control method thereof.

[0004]2. Description of the Related Art

[0005]A display apparatus having a television function generally receives
various external signals from an external device besides terrestrial
broadcasting. Such an external device, which is connected to an input
terminal of the display apparatus and supplies it with external signals,
includes a videocassette recorder (VCR), a digital versatile disk (DVD)
player, a satellite broadcast receiver, a personal computer (PC), and a
game console.

[0006]However, in the process of reproducing the external signals, the
display apparatus may fail to receive the external signals due to
environmental factors or poor conditions in connection with the external
device. If the display apparatus fails to receive external signals when
being operated in a TV mode, the display apparatus displays a blue
screen, and if there is no change in the external signal during a
predetermined time, the display apparatus is automatically turned off.

[0007]On the other hand, if the display apparatus fails to receive
external signals when being operated in an external device mode with one
of the external devices such as VCR, DVD, satellite broadcast receiver,
PC, and game console, the display apparatus displays a message that the
cable connection condition should be checked.

[0008]However, if the display apparatus fails to receive external signals
due to environmental factors, the user is required to directly change an
input terminal of the display apparatus to an input terminal capable of
receiving external signals, which causes inconvenience to the user.

SUMMARY OF THE EXEMPLERY EMBODIMENTS OF THE INVENTION

[0009]Exemplary embodiments of the present invention overcome the above
disadvantages and other disadvantages not described above. Also, the
present invention is not required to overcome the disadvantages described
above, and an exemplary embodiment of the present invention may not
overcome any of the problems described above.

[0010]The present invention provides a display apparatus which is capable
of recognizing an input source even if input signals are detected from
the input source late.

[0011]Consistent with an aspect of the present invention, there is
provided a display apparatus which comprises a signal detector which
checks a plurality of input sources in sequence for a predetermined basic
time and detects signals input from the plurality of input sources, and a
controller which controls the signal detector to adjust the basic time
and recheck the plurality of input sources if no signal is detected
within the basic time.

[0012]The signal detector may check the plurality of input sources in
predetermined order.

[0013]The controller may apply a predetermined maximum allowable time if
no signal is detected within the basic time.

[0014]The signal detector may perform the detecting operation a
predetermined number of times, and, if no signal is detected for the
predetermined number of times, the controller may apply the predetermined
maximum allowable time to the last checking phase of each of the
plurality of input sources.

[0015]The controller may calculate a maximum necessary time which is
required until signals are input from each of the plurality of input
sources within the maximum allowable time.

[0016]The display apparatus may further comprise a storage unit which
stores a reference time which is defined considering the maximum
necessary time, and the controller may control the signal detector to
detect signals by applying the stored reference time to each of the
plurality of input sources.

[0017]Consistent with an aspect of the present invention, a control method
of a display apparatus comprises checking a plurality of input sources in
sequence for a predetermined basic time and detecting signals input from
the plurality of input sources, and if no signal is detected within the
basic time, adjusting the basic time and rechecking the plurality of
input sources.

[0018]The detecting operation may check the plurality of input sources in
a predetermined order.

[0019]The rechecking operation may apply a predetermined maximum allowable
time if no signal is detected within the basic time.

[0020]The detecting operation may be performed a predetermined number of
times, and, if no signal is detected for the predetermined number of
times, the rechecking operation may apply the predetermined maximum
allowable time to the last checking phase of each of the plurality of
input sources.

[0021]The rechecking operation may calculate a maximum necessary time
which is required until signals are input from each of the plurality of
input sources within the maximum allowable time.

[0022]The control method may further comprise storing a reference time
which is defined considering the maximum necessary time, and detecting
signals by applying the stored reference time to each of the plurality of
input sources.

[0023]Accordingly, since the time for detecting input signals from an
external input source can be adjusted, an input source from which input
signals are detected late can be recognized.

[0024]Additional and/or other aspects and advantages of the invention will
be set forth in part in the description which follows and, in part, will
be obvious from the description, or may be learned by practice of the
invention.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

[0025]The above and/or other aspects of the present invention will be more
apparent by describing certain exemplary embodiments of the present
invention with reference to the accompanying drawings, in which:

[0026]FIG. 1 is a view of a display system consistent with an exemplary
embodiment of the present invention;

[0027]FIG. 2 is a block diagram of a display apparatus consistent with an
exemplary embodiment of the present invention;

[0028]FIG. 3 is a detailed block diagram of the display apparatus of FIG.
2;

[0029]FIGS. 4A and 4B are views to explain detecting a maximum necessary
time consistent with an exemplary embodiment of the present invention;
and

[0030]FIG. 5 is a flowchart outlining a control method of a display
apparatus consistent with an exemplary embodiment of the present
invention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0031]Certain exemplary embodiments of the present invention will now be
described in greater detail with reference to the accompanying drawings.

[0032]In the following description, same drawing reference numerals are
used for the same elements even in different drawings. The matters
defined in the description, such as detailed construction and elements,
are provided to assist in a comprehensive understanding of the invention.
Thus, it is apparent that the exemplary embodiments of the present
invention can be carried out without those specifically defined matters.
Also, well-known functions or constructions are not described in detail
since they would obscure the invention with unnecessary detail.

[0033]FIG. 1 is a view of a display system according to an exemplary
embodiment of the present invention. Referring to FIG. 1, a display
system comprises a display apparatus 100 and a plurality of input sources
10, 20, and 30 which transmit input signals to the display apparatus 100.

[0034]The display apparatus 100 receives video and audio signals from the
plurality of input sources 10, 20, and 30 and displays the signals. The
plurality of input sources, recited herein, may be a computer, a digital
versatile disc (DVD) player, a video cassette recorder (VCR), or a
blue-ray player.

[0035]When the display apparatus 100 turns on/off, the display apparatus
100 may fail to receive signals due to environmental factors such as
disconnection of the cable from a currently selected input terminal or
poor conditions in connection with an external device to a terminal. If
signals are not received through a current input terminal, the display
apparatus provides a function of selecting another input terminal capable
of receiving signals. Hereinafter, this function is referred to as an
`input source conversion mode` for the convenience of explanation.

[0036]The input source conversion mode may be an automatic input source
conversion mode in which the display apparatus 100 automatically selects
an input terminal capable of receiving signals. That is, in the automatic
input source conversion mode, depending on whether input signals are
received from a selected input source, the display apparatus 100 checks
next input sources in sequence, and, if input signals are detected, the
input signals are automatically output to the display apparatus 100.

[0037]The input source conversion mode may include a manual input source
conversion mode in which a user is allowed to select a desired input
terminal from the plurality of input terminals through which signals are
received.

[0038]In the manual input source conversion mode, the display apparatus
100 enables a user to select an input terminal through which signals are
received. For example, a list of input terminals through which signals
are received is displayed in an on screen display (OSD) method so that
the user may select a desired input terminal. However, in the manual
input source conversion mode, if there is only one source through which
signals are input among the plurality of input sources, the signals are
automatically output.

[0039]Hereinafter, the automatic input source conversion mode will be
mainly described for the convenience of explanation, but it is obvious to
an ordinary skilled person in the related art that the following
exemplary embodiments are applicable to the manual input source
conversion mode.

[0040]The automatic input source conversion mode may be switched on/off by
the user.

[0041]Accordingly, if the automatic input source conversion mode is not
selected, the display apparatus 100 displays a no-signal condition. That
is, a message such as "No Signal" and "Check Signal Cable" may be
displayed or a blanking image may be displayed in order to inform the
user that no signal is received through a currently selected input
terminal.

[0042]Hereinafter, the display apparatus 100 will be described on the
assumption that the automatic input source conversion mode is switched on
by the user.

[0043]FIG. 2 is a block diagram of a display apparatus 200 according to an
exemplary embodiment of the present invention. Referring to FIG. 2, a
display apparatus 200 comprises a signal detector 210, a controller 220,
and a storage unit 230.

[0044]The signal detector 210 detects signals input from a plurality of
input sources. The signal detector 210 checks the plurality of input
sources in sequence for a predetermined basic time to detect input
signals. In this exemplary embodiment, the basic time is pre-defined but
it may be changed by the user according to various circumstances.

[0045]The controller 220 controls the signal detector 210 to adjust the
predetermined basic time and recheck the plurality of input sources if no
signal is detected by the signal detector 210 within the predetermined
basic time.

[0047]For example, if three input sources, input source 1, input source 2,
and input source 3, are connected and if the signal detection order is
set to the order of input source 1, input source 2, and input source 3,
the signal detector 210 checks the input sources in order of "input
source 1→input source 2→input source 3→input source
1→input source 2→input source 3 . . . input source
1→input source 2→intput source 3". However, this is merely
an example and various checking methods such as checking each input
source two times and then checking the input sources in sequence or
checking the input source at intervals may be used.

[0048]The order of checking the input sources is pre-defined in this
embodiment, but the order may be changed by the user according to various
circumstances. Also, it is possible to check accumulative selection
frequency for each input source and change the order of checking input
sources according to the accumulative selection frequency. That is,
according to the result of checking accumulative frequency of input
signals, a priority of each input source is determined from the most
frequently used input source to the least frequently used input source.

[0049]If no input signal is detected within the predetermined basic time,
the controller 220 applies a predetermined maximum allowable time and
calculates a maximum necessary time which is required until input signals
are input from each input sources.

[0050]The signal detector 210 may perform the detecting operations a
predetermined number of times, and, if no input signal is detected for
the predetermined number of times, the controller 220 applies the
predetermined maximum allowable time to the last checking phase of each
input source considering the predetermined number of times.

[0051]For example, if the number of times that the input signal detecting
operations are performed is set to 12, the signal detector 210 checks
each input source in sequence four times in order of "input source 1
(basic time applied)→input source 2 (basic time
applied)→input source 3 (basic time applied) . . . input source 1
(basic time applied)→input source 2 (basic time
applied)→input source 3 (basic time applied)→input source 1
(maximum allowable time applied)→input source 2 (maximum allowable
time applied)→input source 3 (maximum allowable time applied)",
and applies the predetermined maximum allowable time to the fourth
checking phase of each input source. However, this is merely an example
and the maximum allowable time can be applied to a previous phase as well
as the last detecting phase of each input source.

[0052]The storage unit 230 stores a reference time that is set considering
the maximum necessary time which is required until signals are input from
each of the plurality of input sources. The reference time is defined as
a time used to detect signals instead of the basic time if the automatic
input source conversion mode is applied later.

[0053]If the calculated maximum necessary time is shorter than the basic
time, the controller 220 determines the basic time as a reference time.
Also, if the calculated maximum necessary time is longer than the basic
time, the maximum necessary time is determined as a reference time. The
above exemplary embodiment will be described below in greater detail with
reference the drawings.

[0054]If the automatic input source conversion mode is applied after the
reference time is stored, the controller 220 controls the signal detector
210 to detect signals by applying the stored reference time to each of
the plurality of input sources.

[0055]FIG. 3 is a detailed block diagram of the display apparatus of FIG.
2. Referring to FIG. 3, the display apparatus 200 comprises the signal
detector 210, the controller 220, the storage unit 230, an input unit
240, a signal processor 250, and a display unit 260. Regarding the same
components as those illustrated in FIG. 2, detailed description will be
omitted.

[0056]The signal detector 210 detects input signals input from a plurality
of input sources through the input unit 240. The signal detector 210
checks the plurality of input sources for a predetermined basic time in a
predetermined order to detect input signals. That is, if no signal is
detected from a selected input source, input signals are detected by
checking another input source in the predetermined order.

[0057]If no input signal is detected from at least one of the plurality of
input sources within the predetermined basic time by the signal detector
210, the controller 220 controls the signal detector 210 to adjust the
predetermined basic time and recheck the plurality of input sources. If
input signals are detected by the signal detector 210 within the
predetermined basic time, the controller 220 controls the signal
processor 250 and the display unit 260 to process and display the
detected signals.

[0058]More specifically, if no input signal is detected within the basic
time, the controller 220 applies a predetermined maximum allowable time
and calculates a maximum necessary time which is required until signals
are input from each of the plurality of input sources.

[0059]Also, the signal detector 210 performs the detecting operations a
predetermined number of times, and if no input signal is detected for the
predetermined number of times, the controller 220 applies the
predetermined maximum allowable time to the last checking phase of each
of the plurality of input sources.

[0060]The storage unit 230 stores a reference time which is defined
considering the maximum necessary time required until signals are input
from each of the plurality of input sources. The storage unit 230 may be
realized as an electrically erasable programmable read-only memory
(EEPROM) or FLASH ROM to store data.

[0061]If the calculated maximum necessary time is shorter than the basic
time, the controller 220 determines the basic time as a reference time.
Also, if the calculated maximum necessary time is longer than the basic
time, the controller 220 determines the maximum necessary time as a
reference time.

[0062]If the automatic input source conversion mode is applied after the
reference time is stored in the storage unit 230, the controller 220
controls the signal detector 210 to detect signals by applying the
reference time stored for each of the plurality of input sources.

[0064]The input unit 240 may be a plurality of ports into which connection
cables connected with the input sources are inserted. For example, each
port may be a dedicated port for PC analog signals, PC digital signals,
TV, VIDEO, S-VIDEO, Component, Digital TV (DTV). Also, the input unit 240
may include a digital signal dedicated port for receiving digital signals
and an analog signal dedicated port for receiving analog signals.

[0065]The signal processor 250 converts the signals input through the
input unit 240 into signals of a format which can be processed by the
display unit 260.

[0066]The signal processor 250 may include various components for
processing signals, such as a decoder to decode composite video broadcast
signals or S-Video signals, an A/D converter to convert analog signals of
component signals or PC signals into digital signals, and a transition
minimized differential signaling (TMDS) receiver to divide DVI-signals
into R, G, B digital signals and H/V signals.

[0067]Also, the signal processor 250 may include a scalor which scales the
converted signals to be suitable for output standards of the display unit
260, such as vertical frequency, resolution, and aspect ratio of the
display unit 260.

[0068]The display unit 260 displays video signals processed by the signal
processor 250 on the screen. The display unit 260 may be of various types
such as digital light processing (DLP), liquid crystal display (LCD), or
plasma display panel (PDP).

[0069]If the signal detector 210 detects signals from at least one input
source by applying the predetermined maximum allowable time to the last
checking phase of each of the plurality of input sources 10, 20, and 30,
the controller 220 causes the detected signals to be displayed on the
display unit 260. In this case, the signal detector 210 continues to
perform the last checking operation for each input source if the signals
have been detected from at least one input source. Also, a message, "In
the process of detecting signals", may be displayed on the display unit
260 until the last detecting operation for each of the plurality of input
sources 10, 20, and 30 is completed, and the selected input signals may
be displayed after all checking operations for each of the input sources
are completed.

[0070]If a priority is allocated to the plurality of input sources 10, 20
and 30 but if signals are detected from one of the plurality of input
sources 10, 20, and 30, the image is displayed according to the priority.
However, according to circumstances, at least one of the checked input
signals may be arbitrarily selected and displayed.

[0071]For example, as a result of applying the maximum allowable time, 10
seconds, to the last checking phase to detect signals since no signal is
detected within the basic time, 3 seconds, if signals are detected from
input source 2 at 6 seconds and detected from input source 3 at 2
seconds, the storage unit 230 stores the maximum necessary time of input
source 2, 6 seconds, as a reference time since the maximum necessary time
is longer than the basic time, and stores the basic time of input source
3, 3 seconds, as a reference time since the maximum necessary time, 2
seconds, is shorter than 3 seconds.

[0072]Such a stored reference time is substituted for the basic time if
the automatic input source conversion mode is applied later. That is,
input source 1 is applied with the basic time, 3 seconds, as it is since
the maximum necessary time is not detected in input source 1, input
source 2 is applied with the maximum necessary time, 6 seconds, as a
reference time and input source 3 is applied with the basic time, 3
seconds, as a reference time.

[0073]If no signal is detected even within the newly set reference time in
the input source conversion mode, the reference time is reset according
to the above-described method.

[0074]The automatic conversion mode has been mainly described above, but
it is obvious to an ordinary skilled person in the related art that the
present invention is applicable to a manual conversion mode.

[0075]FIGS. 4A and 4B illustrate an example of detecting a maximum
necessary time according to an exemplary embodiment of the present
invention.

[0076]Referring to FIG. 4A, a basic time required for detecting signals
from the plurality of input sources, input source 1, input source 2, and
input source 3, is set to 3 seconds, and if no signal is detected within
the basic time for a predetermined number of times, a maximum allowable
time applied to the last checking phase of each input source is set to 10
seconds.

[0077]In the above example, in the last checking phase in which 10 seconds
are applied as a maximum allowable time, no signal is detected from input
source 1, signals are detected from input source 2 at 6 seconds, and
signal are detected from input source 3 at 2 seconds.

[0078]Referring to FIG. 4B, if the number of times that input sources are
checked is set to 12 and the detection is made in order of input sources
1, 2, and 3, the input sources are checked in sequence in the order of
"input source 1 (1st)→input source 2 (2nd)→input
source 3 (3rd)→input source 1→input source
2→input source 3 . . . input source 1 (10th)→input
source 2 (11th)→input source 3 (12th).

[0079]If no signal is detected until the 9th checking phase, i.e.,
before the last checking phase of each input source, the maximum
allowable time, 10 seconds, is applied to the last checking phases
(10th to 12th) of each of input sources to detect signals.

[0080]In the last checking phase of each input source, no signal is
detected from input source 1, signals are detected from input source 2 at
6 seconds, and signals are detected from input source 3 at 2 seconds.

[0081]In this case, the storage unit 230 stores the basic time (3 seconds)
of input source 1, from which no signal is detected in the last phase, as
a reference time for input source 1, stores the maximum necessary time (6
seconds) of input source 2, which is longer than the basic time (3
second), as a reference time for input source 2, and stores the basic
time (3 seconds) of input source 3, the maximum necessary time (2
seconds) of which is shorter than the basic time (3 seconds), as a
reference time for input source 3.

[0082]Such a stored reference time is substituted for the basic time for
detecting signals if the input source conversion mode is applied later.

[0083]In this exemplary embodiment, the automatic input source conversion
mode has been mainly described, but the present invention is applicable
to the manual input source conversion mode.

[0084]FIG. 5 is a flowchart outlining a control method of a display
apparatus according to an exemplary embodiment of the present invention.

[0085]Referring to FIG. 5, a plurality of input sources is checked in
sequence for a predetermined basic time (operation S510). In this
operation, the input sources may be checked in a predetermined order a
predetermined number of times. For example, if the basic time is set to 3
seconds, the detection is made in order of input sources 1, 2, and 3, and
the number of times that the detecting operation is performed is set to
12, the input sources are checked in order of "input source
1→input source 2→input source 3→input source
1→input source 2→input source 3 . . . input source
1→input source 2→input source 3".

[0086]Next, it is checked whether signals are detected from the plurality
of input sources (operation S520)

[0087]If no signal is detected from the plurality of input sources within
the basic time (operation S520: N), it is checked whether the number of
times that the input sources have been checked exceeds a predetermined
number or not (operation S530).

[0088]If the number of times that the input sources have been checked
exceeds a predetermined number (operation S530: Y), the plurality of
input sources are checked by applying a predetermined maximum allowable
time (operation S540).

[0089]For example, if the total number of times that the detecting
operation is performed is set to 12 and if the number of times that the
input sources have been checked exceeds 10, the plurality of input
sources are checked by applying the maximum allowable time, for example,
10 seconds from the 10th checking phase.

[0090]If signals are detected within the predetermined maximum allowable
time (operation S550: Y), a maximum necessary time which is required
until signals are input from each of the input sources is stored
(operation S560). That is, if signals are detected from input source 2 at
6 seconds as a result of applying the maximum allowable time, 10 seconds,
to the last checking phase of each of the input sources, the maximum
necessary time, 6 seconds, is stored for input source 2.

[0091]A reference time which is defined considering the maximum necessary
time which is required until signals are input from each of the plurality
of input sources may be stored. More specifically, if the calculated
maximum necessary time is shorter than the basic time, the basic time is
set as a reference time, and if the calculated maximum necessary time is
longer than the basic time, the maximum necessary time is set as a
reference time.

[0092]For example, as a result of applying the maximum allowable time, 10
seconds, to the last phase since no signal is detected within the basic
time, 3 seconds, if signals are detected from input source 2 at 6 seconds
and signals are detected from input source 3 at 2 seconds, the storage
unit 230 stores the maximum necessary time, 6 seconds, as a reference
time for input terminal 2 because the maximum necessary time is longer
than the basic time, 3 seconds, and stores the basic time, 3 seconds, as
a reference time for input terminal 3 because the maximum necessary time,
2 seconds, is shorter than the basic time.

[0093]Such a stored reference time is substituted for the basic time if
the input source conversion mode is applied later. That is, the basic
time, 3 seconds, is applied to input source 1 since no maximum necessary
time is detected in input source 1, the maximum necessary time, 6
seconds, is applied to input source 2 since the maximum necessary time is
longer than the basic time, 3 seconds, and the basic time, 3 seconds, is
applied to input source 3 since the maximum necessary time, 2 seconds, is
shorter than the basic time.

[0094]Since the time for detecting input signals from an external input
source can be adjusted, an input source from which input signals are
detected late can be recognized.

[0095]The foregoing exemplary embodiments and advantages are merely
exemplary and are not to be construed as limiting the present invention.
The present teaching can be readily applied to other types of
apparatuses. Also, the description of the exemplary embodiments of the
present invention is intended to be illustrative, and not to limit the
scope of the claims, and many alternatives, modifications, and variations
will be apparent to those skilled in the art.